Method for preparing a motor vehicle for a crash test

ABSTRACT

A method for preparing a motor vehicle for a crash test is disclosed. The method subjects the motor vehicle to a sequence of different tests and provides a system of staged modifications that can be made to help the motor vehicle pass the current test without invalidating test results obtained earlier in the sequence. In some cases, this method can be used to confirm that a particular motor vehicle qualifies for a certain crash test routine.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional patentapplication No. 60/614,509, filed on Jan. 6, 2005, which is herebyincorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the field of motor vehicle restraint systems,and more particularly, to a method for crash testing a motor vehicle.

2. Related Art

Currently, some cars, trucks and vans provide some kind of supplementalrestraint system (SRS). Often, these supplemental restraint systems takethe form of inflatable devices or restraints. In some cases, airbags areused. The following related art references provide a general backgroundof the field.

Cooper (U.S. Pat. No. 6,696,933) discloses an air bag system with abiomechanical grey zone. The biomechanical grey zone is an attempt tocomply with recent legislative changes that require airbags to restrainwomen and children as well as adult males. To help restrain women andchildren, Cooper proposes the use of a system where air bags includemulti-level inflators that can adjust the inflation characteristics ofthe air bag. The biomechanical zone is defined as a region where it isacceptable to deploy the air bag using either a low power inflator or ahigh power inflator. While the use of biomechanical grey zones may helpto comply with new governmental requirements, the grey zones introduceuncertainty in the deployment characteristics of the air bag and thismakes system design and testing difficult. The Cooper reference isincorporated by reference in its entirety.

Corrado et al. (U.S. Pat. No. 6,249,729) teaches an occupancy sensingsystem for an automobile. The system is used in conjunction with anairbag deployment system to determine the nature, location and motionparameters of an occupant within the vehicle interior. These parametersare determined by ultrasound and/or infrared sensors. The systemestablishes criteria for airbag disablement or for modified airbagdeployment based on sensor information. In particular, Corrado teachesthe use of a Keep Out Zone (KOZ) within the vehicle interior relative tothe dashboard or instrument panel. Analyzing the relative location of anoccupant with respect to the Keep Out Zone can be used to determinewhether the airbag deployment is disabled or modified.

Wang et al. (U.S. Pat. No. 6,662,092) teaches a control method fordeploying an air bag using fuzzy logic. Wang attempts to provide a fuzzylogic deployment system that is more direct than previous fuzzy logicsystems and where the calibration process if more user friendly. Themethod uses a deployment control algorithm to determine whether certainstages are deployed based on certain thresholds related to predictedoccupant movement and crash severity.

There is currently a need for a way to increase the predictability ofthe deployment of an inflatable restraint to improve occupant safety andto simplify the process of crash testing the motor vehicle.

SUMMARY OF THE INVENTION

A system and method for crash testing a motor vehicle is disclosed. Theinvention can be used in connection with a motor vehicle. The term“motor vehicle” as used throughout the specification and claims refersto any moving vehicle that is capable of carrying one or more humanoccupants and is powered by any form of energy. The term motor vehicleincludes, but is not limited to cars, trucks, vans, minivans, SUV's,motorcycles, scooters, boats, personal watercraft, and aircraft.

Generally, the related art teaches systems and methods for a singledeployment event and focus on correctly making a single deploymentdecision. In contrast, one aspect of the present invention is directedto providing a novel deployment map that applies to a number ofdifferent deployment scenarios and conditions. This novel map can helpimprove the predictability of a deployment of an inflatable restraint,and this predictability can help designers and engineers improveoccupant safety over a wide range of different collision scenarios andconditions. In another aspect, the present invention is directed to amethod of qualifying a motor vehicle to use the novel deployment map.

In another aspect, the invention provides a method for qualifying amotor vehicle for a crash test routine comprising the steps of:determining whether the motor vehicle passes a first test related to ahypothetical child passenger; and altering the motor vehicle using afirst stage of modifications if the motor vehicle fails the first test.

In another aspect, the invention provides a step of determining whetherthe motor vehicle passes a second test related to a passenger; andaltering the motor vehicle using a second stage of modifications if themotor vehicle fails the second test; and wherein the second stage ofmodifications is different than the first stage of modifications.

In another aspect, the invention provides a step of determining whetherthe motor vehicle passes a third test related to an out of positionpassenger; and altering the motor vehicle using a third stage ofmodifications if the motor vehicle fails the third test; and wherein thethird stage of modifications is different than the first stage ofmodifications and the second stage of modifications.

In another aspect, the invention provides a step of determining whetherthe motor vehicle passes a fourth test related to a crash test conductedat a first speed; and altering the motor vehicle using a fourth stage ofmodifications if the motor vehicle fails the fourth test; and whereinthe fourth stage of modifications is different than the first stage ofmodifications, the second stage of modifications and the third stage ofmodifications.

In another aspect, the invention provides a step of determining whetherthe motor vehicle passes a fifth test related to a crash test conductedat a second speed; and altering the motor vehicle using a fifth stage ofmodifications if the motor vehicle fails the fifth test; wherein thesecond speed is greater than the first speed; and wherein the fifthstage of modifications is different than the first stage ofmodifications, the second stage of modifications, the third stage ofmodifications and the fourth stage of modifications.

In another aspect, the invention provides a step of determining whetherthe motor vehicle passes a sixth test related to a female crash testconducted at the second speed.

In another aspect, the invention provides a method for preparing a motorvehicle for a crash test routine comprising a first test and a secondtest, the first test producing first test results; wherein first stagemodifications are available to help pass the first test; wherein secondstage modifications are available to help pass the second test; andwherein the second stage modifications are different than the firststage modifications.

In another aspect, changes made using the second stage modificationsmaintain the validity of the first test results.

In another aspect, first stage modifications include modifying a shapeof an instrument panel associated with the motor vehicle.

In another aspect, first stage modifications include modifying a firstthigh contact point.

In another aspect, first stage modifications include modifying a heightof a seat associated with the motor vehicle.

In another aspect, wherein first stage modifications can be made byoptionally changing any one of the group consisting essentially of:modifying a shape of an instrument panel associated with the motorvehicle, modifying a first thigh contact point, and modifying a heightof a seat associated with the motor vehicle.

In another aspect, wherein second stage modifications include moving aposition of a knee bolster associated with the motor vehicle.

In another aspect, wherein second stage modifications include moving aposition of a windshield associated with the motor vehicle.

In another aspect, wherein second stage modifications include adjustinga stiffness of a knee bolster associated with the motor vehicle.

In another aspect, wherein second stage modifications can be made byoptionally changing any one of the group consisting essentially of:moving a position of a knee bolster associated with the motor vehicle,moving a position of a windshield associated with the motor vehicle, andadjusting a stiffness of a knee bolster associated with the motorvehicle.

In another aspect, wherein the first test includes determining whether ahypothetical child enters a No Good Zone.

In another aspect, wherein the No Good Zone is associated with apassenger side inflatable device.

In another aspect, wherein the second test includes determining whethera hypothetical male passenger clears a windshield associated with themotor vehicle.

In another aspect, the second test includes determining a pelvic strokeof a hypothetical male passenger.

Other systems, methods, features and advantages of the invention willbe, or will become, apparent to one with skill in the art uponexamination of the following figures and detailed description. It isintended that all such additional systems, methods, features andadvantages be included within this description, be within the scope ofthe invention, and be protected by the following claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood with reference to the followingdrawings and description. The components in the figures are notnecessarily to scale, emphasis instead being placed upon illustratingthe principles of the invention. Moreover, in the figures, likereference numerals designate corresponding parts throughout thedifferent views.

FIG. 1 is a schematic diagram of a preferred embodiment of a method forimproving a crash test routine for a motor vehicle.

FIG. 2 is a schematic diagram of a conventional firing map for aninflatable restraint.

FIG. 3 is a schematic diagram of a preferred embodiment of a firing mapfor an inflatable restraint.

FIG. 4 is a table of a series of crash tests when using a conventionalfiring map.

FIG. 5 is a table of a series of crash tests when using a preferredembodiment of a firing map.

FIG. 6 is a flow diagram of a preferred embodiment of a method forqualifying a motor vehicle for a crash test routine.

FIG. 7 is an enlarged schematic diagram of a preferred embodiment ofstep 604 of FIG. 6.

FIG. 8 is an enlarged schematic diagram of a preferred embodiment ofstep 608 of FIG. 6.

FIG. 9 is an enlarged schematic diagram of a preferred embodiment ofstep 616 of FIG. 6.

FIG. 10 is a schematic diagram of a preferred embodiment of a No GoodZone.

FIG. 11 is a schematic diagram of a failed crash test.

FIG. 12 is a schematic diagram of a preferred embodiment of a crash testthat has been passed.

FIG. 13 is a schematic diagram of a preferred embodiment of an out ofposition child.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

FIG. 1 is a flow diagram of a preferred embodiment of a method ofimproving a crash test regiment for a motor vehicle. The method shown inFIG. 1 can include the following steps. The method begins with step 102where a new firing map is designed. This new firing map helps tosimplify the firing conditions of an inflatable restraint and reduceoccupant injury. The simplified algorithm or firing map can help makethe deployment conditions of the inflatable restraint more predictableand this help provide a supplemental restraint system that is morereliable and easier to test. This predictability also helps designersimprove occupant safety. Another benefit of the new firing map is thatit can help reduce the number of vehicles required to comply withgovernment-mandated crash tests. In some cases, this reduction issubstantial.

After the new firing map has been designed, the method can proceed tostep 104 where a motor vehicle is qualified for using the new firingmap. In step 104, the process helps to identify which motor vehicles canaccept the new map and can also help tune or modify a motor vehicle sothat it can become a motor vehicle capable of using the new firing map.

After the motor vehicle has been qualified to use the new firing map,the motor vehicle is then subjected to a simplified crash test routinein step 106. Preferably, step 106 includes the process of actuallyconducting real world crash tests with actual motor vehicles and crashtest dummies.

FIG. 2 is a schematic diagram of a conventional firing map 200 for aninflatable restraint. The conventional firing map 200 includes threedeployment scenarios depending on the type of impact. The three types ofimpact are a conventional flat barrier scenario 202, a conventionalangled barrier scenario 204 and a conventional offset barrier scenario206. In each of the scenarios, the conventional firing map 200 alsodeploys the inflatable restraints differently depending on the speed ofthe impact. Generally, conventional firing map 200 considers the speedof the impact and the type of impact to determine how or if theinflatable restraint is deployed.

In the conventional flat barrier scenario 202, conventional firing map200 includes three different deployment options, which are related tocorresponding regions in the bar graph representing conventional flatbarrier scenario 202. The first deployment option is a no fire optionand this first option occurs in region 208. A second deployment optionis a delay fire option, and this second option occurs in region 210. Thethird deployment option is a simultaneous fire option that occurs inregion 212.

Generally, inflatable restraint systems can include two charges, a lowpower charge and a high power charge. The high power charge is generallydesigned to provide a low energy deployment that is suitable for smallerand less massive occupants, for example, a woman with physicalcharacteristics similar to an AF5% crash test dummy. The low powercharge is generally used to supplement the energy of the high powercharge, and when these two charges are deployed simultaneously, theyproduce a high energy deployment that is suitable for larger and moremassive individuals, for example, a male with physical characteristicssimilar to an AM50% crash test dummy.

A delay deployment can be conducted in many different ways. The systemcan delay deploying the inflatable restraint in the following ways: thesystem can immediately deploy the high power charge and delay deployingthe low power charge, the system can delay first and then deploy the twocharges simultaneously, or the system can deploy the low power chargeimmediately and delay deploying the high power charge. In a simultaneousdeployment, the system deploys both the low power charge and the highpower charge at the same time to inflate the restraint very quickly.

In some embodiments, a simultaneous deployment can include a slightdelay. In these embodiments, the high power charge is initiallydeployed, and then a slight delay is provided. This delay can be used toprovide the system with a little more time to decide whether to deploythe second low power charge. In some cases, the system has determinedthat the high power charge needs to be deployed. The slight delay can beused to retrieve information from other sensors or perform othercomputations. These steps can be used by the system to decide whether toalso deploy the low power charge. This slight delay can range from about0 to 10 milliseconds and in an exemplary embodiment, the delay is about5 milliseconds.

The conventional firing map 200 includes transition zones between twoadjacent deployment regions. Considering conventional flat barrier 202,a first transition zone 214 is disposed between first region 208 andsecond region 210. This first transition zone 214 is bounded, on the lowspeed end, at about 13 km/h and on the high speed end at about 19 km/h.

This first transition zone 214 determines the deployment characteristicsfor the inflatable restraint where the passenger or driver is unbelted.First transition zone 214 graphically represents the percentage chancebetween first region 208 and second region 210. In conventional map 200,first region 208 corresponds to a no fire condition and second region210 corresponds to a delay fire condition. Thus, first transition zone214 graphically represents the percentage chance that the inflatabledevice will either not deploy (no fire) or will deploy in a delay mode.

As shown in FIG. 2, at the low end of first transition zone 214, the bargraph representing the conventional flat barrier scenario 202 is almostcompletely represented by first region 208. This means that there isalmost a 100% chance that the deployment condition associated with firstconventional region 208 will occur. Since first conventional region 208represents a no fire condition, there virtually no chance that theinflatable device will deploy at the low end of first transition zone214.

At the opposite end of first transition zone 214, at about 19 km/h, thebar graph representing first scenario 202 is almost completelyrepresented by second region 210. Since second region 210 corresponds toa delay fire condition, it is virtually assured that inflatablerestraint will deploy in a delay fire mode. At speeds between 13 km/hand 19 km/h, there is a generally linear relationship between speed andthe likelihood that the inflatable device will be deployed in a delaymode. Generally, as speed increases, it becomes more and more likelythat the inflatable restraint will be deployed in a delay mode.

Conventional flat barrier scenario 202 also includes a second transitionzone 216. This second transition zone 216 extends from a low end ofabout 13 km/h to a high end of about 26 km/h. In order to accuratelyshow first transition zone 214, FIG. 2 shows only a portion of secondtransition zone 216, the slope of which should continue until 13 km/h.This second transition zone relates to a belted occupant, either driveror passenger. Second transition zone 216 provides the probability thatthe inflatable device will either not deploy or will deploy in a delaymode. Again, like first transition zone 214, the percentage chance ofeither a no fire condition or a delay fire condition is graphicallyrelated to ratio of the first region 208 compared to the second region210 at a given speed.

Conventional flat barrier scenario 202 includes a third transition zone218. This third transition zone 218 is disposed between second region210 and third region 212 and provides the percentage chance of either adelay mode deployment or a simultaneous deployment.

Third transition region starts at about 30 km/h and extends to about 37km/h. Similar to the first and second transition regions, thirdtransition region 218 provides a percentage chance that the inflatabledevice will deploy in accordance with the pattern associated with secondregion 210 or third region 212. Recall that second region 210 isassociated with a delay fire condition and third region 212 isassociated with a simultaneous fire condition. Because of theseassociations, third transition zone 218 graphically represents thepercentage chance that an inflatable device will deploy in a delay firemode or a simultaneous fire mode.

As shown in conventional flat barrier scenario 202, the percentagechance that the inflatable device will deploy in a simultaneous firemode increases as the speed of the impact increases. At about 37 km/h,it is a virtual certainty that the inflatable device will deploy in asimultaneous mode and at speeds above 37 km/h, the inflatable device isdesigned to deploy in simultaneous mode.

Conventional angle barrier scenario 204 includes three regions, firstregion 208, second region 210 and third region 212 corresponding tothree different deployment patterns for an inflatable restraint.Conventional angle barrier scenario 204 includes a fourth transitionzone 220 disposed between first region 208 and second region 210. Fourthtransition zone 220 extends from a low end of about 13 km/h to a highend of about 19 km/h.

Fourth transition zone 220 is similar to first transition zone 214. Asshown in FIG. 2, at the low end of fourth transition zone 220, the bargraph representing the angle barrier scenario 204 is almost completelyrepresented by first conventional region 208. This means that there isalmost a 100% chance that the deployment condition associated with firstconventional region 208 will occur. Since first conventional region 208represents a no fire condition, there virtually no chance that theinflatable device will deploy at the low end of fourth transition zone220.

At the opposite end of fourth transition zone 220, at about 19 km/h, thebar graph representing second scenario 204 is almost completelyrepresented by second region 210. Since second region 210 corresponds toa delay fire condition, it is virtually assured that inflatablerestraint will deploy in a delay fire mode. At speeds between 13 km/hand 19 km/h, there is a generally linear relationship between speed andthe likelihood that the inflatable device will be deployed in a delaymode. Generally, as speed increases, it becomes more and more likelythat the inflatable restraint will be deployed in a delay mode.

Conventional angle barrier scenario 204 also includes a fifth transitionzone 222 disposed between second region 210 and third region 212. Thisfifth transition zone 222 extends from a low end of about 26 km/h to ahigh end of about 32 km/h and provides the percentage chance of either adelay mode deployment or a simultaneous deployment.

Fifth transition zone 222 starts at about 26 km/h and extends to about32 km/h. Similar to other transition zones, fifth transition zone 222provides a percentage chance that the inflatable restraint will deployin accordance with the pattern associated with second region 210 orthird region 212. Recall that second region 210 is associated with adelay fire condition and third region 212 is associated with asimultaneous fire condition. Because of these associations, fifthtransition zone 222 graphically represents the percentage chance that aninflatable restraint will deploy in a delay fire mode or a simultaneousfire mode.

As shown in conventional angle barrier scenario 204, the percentagechance that the inflatable device will deploy in a simultaneous firemode increases as the speed of the impact increases. At about 32 km/h,it is virtual assured that the inflatable restraint will deploy in asimultaneous mode and at speeds above 32 km/h, the inflatable restraintis designed to deploy in simultaneous mode.

Conventional offset barrier scenario 206 includes two regions, firstregion 208 and second region 210. Conventional offset barrier scenario206 does not include a third region. Sixth transition zone 224 isdisposed between first region 208 and second region 210. Sixthtransition zone 224 is larger than some other transition zones andextends from about 26 km/h to about 40 km/h.

As shown in FIG. 2, at the low end of sixth transition zone 224, the bargraph representing the offset barrier scenario 206 is almost completelyrepresented by first conventional region 208. This means that there isalmost a 100% chance that the deployment condition associated with firstconventional region 208 will occur. Since first conventional region 208represents a no fire condition, there virtually no chance that theinflatable restraint will deploy at the low end of sixth transition zone224.

At the opposite end of sixth transition zone 224, at about 40 km/h, thebar graph representing offset barrier scenario 206 is almost completelyrepresented by second region 210. Since second region 210 corresponds toa delay fire condition, it is virtually assured that inflatablerestraint will deploy in a delay fire mode. At speeds between 26 km/hand 40 km/h, there is a generally linear relationship between speed andthe likelihood that the inflatable device will be deployed in a delaymode. Generally, as speed increases, it becomes more and more likelythat the inflatable restraint will be deployed in a delay mode.

Government rules generally require motor vehicles to undergo crashtesting at certain speeds and under certain conditions. Currently, thereare two government regulation zones, a first regulation zone between 32km/h to 40 km/h for unbelted occupants and a second regulation zonebetween 0 km/h and 48, km/h for belted occupants. Motor vehicles sold inthe United States must be subjected to a number of crash tests toestablish passenger and occupant safety in these regulation zones in theevent of a collision.

While transition zones have been used in the past as a way to decide howto deploy an inflatable restraint, they also introduce a number ofproblems. Deployments that occur within transition zones areunpredictable because the transition zones only provide percentagechances of two competing deployment conditions. In some cases, theresponse of a system using conventional firing map 200 is sounpredictable that it is possible for an inflatable restraint to deploytwo different ways in two successive and identical crash tests.

Because the deployment of an inflatable restraint is unpredictable in atransition zone, the system must be tested at the government mandatedspeeds as well as at all endpoints of the transition zone.

In order to minimize the number of crash tests, engineering reasoning isgenerally used and a worst case scenario is tested. Using engineeringreasoning, if a motor vehicle passes a crash test conducted under theworst case, then it can be assumed that the motor vehicle will also passa crash test at under less severe conditions. This is one way tovalidate the response of the system under many different possibleconditions. For example, if a motor vehicle passed a crash test at 40km/h, engineering reasoning dictates that the same motor vehicle,identically prepared and equipped, should pass the same crash test at 35km/h. In fact, the motor vehicle should also pass the same crash test atany speed between 0 and 40 km/h.

Referring to FIG. 4, which is a table of crash tests for conventionalfiring map 200, and FIG. 2, the crash tests that are required can beobserved. The crash tests are preferably conducted in sets, and each setpreferably includes a driver and a passenger. Set 1 is conducted at aspeed of 37 km/h and with a flat barrier collision condition. Set 1 isused to test the occupant safety of a typical female and an AF5% crashtest dummy (which stands for American Female 5 percentile) can be usedto model the behavior of a hypothetical female occupant. Set 1 is anunbelted test, meaning seat belts are not used during the test.

Set 2 is similar to set 1 except that set 2 is used to test the occupantsafety of a typical male and an AM50% crash test dummy (which stands forAmerican Male, 50 percentile) can be used to model the behavior of ahypothetical male. The conditions and attributes of the remaining elevensets of crash tests are self-explanatory from the table shown in FIG. 4.

FIG. 3 is a schematic diagram of a preferred embodiment of firing map300. It has been discovered that with careful design of motor vehicle100, the simultaneous fire mode is not necessary to provide occupantsafety and also meet government crash test requirements. In other words,it is possible to use a delay fire mode to meet government crash testrequirements under conditions where conventional systems use asimultaneous fire mode.

This discovery can be used to create a firing map 300 that is lesscomplex than conventional firing map 200. It is believed that thisdiscovery will help to improve occupant safety because the reduction inthe complexity of the new firing map 300 compared to the conventionalfiring map 200 can provide more predictable deployments of inflatabledevices. This improved predictability can, in turn, be used to betterunderstand the interplay between occupants and the inflatable restraintsystem at various different speeds and collision conditions. This canhelp engineers design safer motor vehicles and inflatable restraintsystems. As a side benefit, this discovery also allows the locations ofthe various transition zones to be selected to prevent overlap with oneor more government regulation zones.

Also, because a simultaneous fire mode is no longer required, thisentire deployment mode can be omitted from firing map 300. In theembodiment shown in FIG. 4, firing map 300 does not include asimultaneous deployment or firing condition. Firing map 300 includesjust two deployment patterns, a no fire mode and a delayed deploymentmode.

Preferably, the various transition zones are carefully selected so thatnone of the transition zones overlaps a regulation zone. In oneembodiment shown in FIG. 3, the transition zones have been moved away orseparated from the regulation zones. This allows the crash test routineto be greatly simplified. Referring to FIG. 5, which is a table of crashtests corresponding to firing map 300 reflected in FIG. 3, differencesbetween this table and the table shown in FIG. 4 are readily apparent.

As shown in FIG. 5, several crash tests are no longer needed. Set 1 isno longer needed because set 3 is conducted at 40 km/h under the sameconditions, namely in delay mode. Note the arrows indicating that newset 3 is conducted in delay mode from the previous no delay mode. Asdiscussed earlier, if a motor vehicle passes a crash test at a higherspeed, then it can be assumed that the motor vehicle will pass the samecrash test at a lower speed. Because the new firing map 300 uses thesame deployment conditions at 40 km/h and 37 km/h, any motor vehicleusing new firing map 300 that passes the 40 km/h crash test should alsopass set 1 as well. For the same reasons, sets 2, 5, 6 and 12 are nolonger required.

Returning to FIG. 1, some embodiments include provisions 104 todetermine if a motor vehicle is qualified to use new firing map 300.Although many different methods can be used to determine if a motorvehicle is qualified to use new firing map 300, the following method ispreferred. Referring to FIG. 6, which is a flow diagram of a preferredembodiment of a method 104 for determining if a motor vehicle isqualified to use new firing map 300, this method can both determine if amotor vehicle is qualified to use new firing map 300 and also helpmodify or “tune” the motor vehicle so it becomes qualified to use newfiring map 300.

Method 104 can include a number of different tests and a number ofmodifications that can be made to help the motor vehicle to pass thosetests. Preferably, these tests and modifications are arrangedsequentially within method 104 in a systematic way so that amodification does not invalidate previous test results.

Preferably, method 104 begins with first test 602. In first test 602,the relative position of a hypothetical child with respect to a No GoodZone (“NGZ”) 1002 is considered. In some cases, a C3Y (child, three yearold) and/or C6Y (child, six year old) dummy is used to model thehypothetical child. Referring to FIG. 10, NGZ 1002 is a zone roughlybetween inflatable restraint lid 1004 and windshield 1006. In someembodiments, NGZ 1002 is defined using particular relative offsets andspacing from various components.

In a preferred embodiment, NGZ 1002 is defined by one or moreboundaries. These boundaries are preselected or predefined distancesfrom various objects or lines. In the embodiment shown in FIG. 10,inflator module 1020 includes an inflator center line 1022. In someembodiments, a boundary is established based on inflator center line1022. In the embodiment shown in FIG. 10, inflator center line boundary1026 is defined as a boundary that is parallel and spaced from inflatorcenter line 1022. The distance can be varied, however, any distance ofabout 30 mm to 200 mm can be used. In an exemplary embodiment, inflatorcenter line boundary 1026 is disposed about 70 mm away from inflatorcenter line 1020 towards or into the passenger cabin of motor vehicle100.

Inflator module 1020 can also include an edge 1024. In some embodiments,a boundary is established based on inflator edge 1024. In the embodimentshown in FIG. 10, inflator edge boundary 1028 is defined as a boundarythat is vertical and horizontally spaced from inflator edge 1024. Thedistance can be varied, however, any distance of about 30 mm to 200 mmcan be used. In an exemplary embodiment, inflator edge boundary 1028 isdisposed about 70 mm away from inflator edge 1024 towards or into thepassenger cabin of motor vehicle 100.

In some embodiments, a boundary can be established based on windshield1006. In the embodiment shown in FIG. 10, windshield boundary 1030 isdefined as a boundary that is roughly parallel to windshield 1006. Thedistance between windshield 1006 and windshield boundary 1030 can bevaried, however, any distance of about 50 mm to 300 mm can be used. Inan exemplary embodiment, windshield boundary 1030 is disposed about 100mm away from windshield 1006 towards or into the passenger cabin ofmotor vehicle 100.

In some embodiments, a boundary can be established based on inflator lid1004. In the embodiment shown in FIG. 10, the arc or range of motion ofthe inflator lid is indicated by 1004. A lid boundary 1032 is defined asa locus of points equally spaced from arc 1004 and disposed outward oraway from inflator module 1020. The distance between inflator lid 1004and lid boundary 1032 can be varied, however, any distance of about 1 mmto 50 mm can be used. In an exemplary embodiment, lid boundary 1032 isdisposed about 10 mm away from arc 1004 towards or into the passengercabin of motor vehicle 100.

One or more of these various different boundaries can be used toestablish NGZ 1002. In an exemplary embodiment, shown in FIG. 10, all ofthe above boundaries are used. However, other embodiments may use moreor less boundaries to establish NGZ 1002.

Referring to FIG. 6, if the hypothetical child passenger is clear of NGZ1002, then the process moves on to step 606. However, if thehypothetical child passenger does not clear NGZ 1002, then the processmoves to step 604.

FIG. 7 is an enlarged view of step 604, and one or more of themodifications shown in FIG. 7 can be made to help motor vehicle 100 passfirst test 602. One option is to modify the Instrument Panel (IP) 1008shape. The shape of IP 1008 can be extended into the passenger cabin tohelp prevent entry of the hypothetical child in to NGZ 1002. Anotheroption is to modify the shape of first thigh bolster or first contactpoint. Another option is to modify the passenger seat height and/orangle. One or more of these options can be used to prevent thehypothetical child occupant from entering NGZ 1002.

Some of these modifications can be seen in FIG. 13, which is a schematicdiagram of a motor vehicle interior and an out of position child 1302.Motor vehicle interior includes a seat 1304. The forward edge 1306 ofseat 1304 generally serves as the first contact point for child 1302. Asshown schematically in FIG. 13, the location of forward edge 1306 and/orthe angle of seat 1304 can be modified to help motor vehicle 100 passfirst test 602.

After these modifications are made, the process returns to first test602 until it has been confirmed that the hypothetical child does notenter NGZ 1002.

After this has been confirmed, the process moves on to step 606, thesecond test, where the process determines whether or not the kinematicarc of an average male passenger will strike windshield 1006. FIGS. 11and 12 are schematic diagrams of examples demonstrating contact withwindshield 1006 and clearance of windshield 1006, respectively. In somecases, an AM50% crash test dummy (which stands for American Male, 50percentile) is used in second test 606. Referring to FIG. 11, crash testdummy 1100 is in a first position 1102 prior to the collision and is ina second position 1104 after the collision. As shown in FIG. 11, crashtest dummy 1100 contacts windshield 1006 in second position 1104. It canalso be observed that the pelvis 1105 of crash test dummy 1100 movesfrom a first position 1106 to a second position 1107 as indicated byarrow 1112 causing an excessive pelvic stroke during the collision. Bothof these incidents are not desirable and would cause the design shown inFIG. 11 to fail second test 606.

Because the motor vehicle failed second test 606, the process would moveto step 608 where stage two modifications can be made. FIG. 8 is anenlarged view of step 608, and from FIG. 8, there are preferably threeavailable stage two modifications that can be made. The Knee Bolster(K/B) 1108 can be moved; the windshield 1106 can be moved forward andaway from the occupant; and finally the stiffness of knee bolster 1108can be adjusted. One or more of the stage two modifications can be made,and eventually the goal is to design the motor vehicle to pass secondtest 606.

FIG. 12 is a preferred embodiment of an example of a motor vehicle thatpasses second test 606. In FIG. 12, crash test dummy 1200 moves from afirst position 1202 prior to the collision to a second position 1204after the collision. It can be observed in FIG. 12, that crash testdummy 1200 clears windshield 1006 and no head contact with windshield1006 occurs. It can also be observed that re-designed knee bolster 1208helps to manage the motion of pelvis 1206 to acceptable levels.

After motor vehicle 100 passes second test 606, the process proceeds tothird test 610 where an Out Of Position (OPP) child passenger is testedwith a delayed firing inflatable restraint. In a preferred embodiment,the firing delay is about 20 to 30 milliseconds. Again, like othertests, a C6Y (child, six year old) dummy can be used for third test 610.If motor vehicle 100 fails third test 610, then the process moves tostep 612, where stage three modifications, including tuning thepassenger side inflatable restraint can be made. After the inflatablerestraint has been tuned, the process returns to third test 610.Preferably, this is done until motor vehicle 100 passes third test 610.

After motor vehicle 100 passes third test 610, the process moves on tofourth test 614. Fourth test 614 determines whether motor vehicle 100can protect occupants during a frontal 40 km/h collision who are notwearing their seat belts. Preferably, both a hypothetical male occupantand a hypothetical female occupant are tested in fourth test 614. Insome embodiments, an AM50% crash test dummy (which stands for AmericanMale, 50 percentile) is used to model the behavior of a hypotheticalmale and an AF5% crash test dummy (which stands for American Female 5percentile) is used to model the behavior of a hypothetical femaleoccupant.

If motor vehicle 100 fails fourth test 614, then the process moves tostep 616 where stage four modifications can be made. FIG. 9 is anenlarged view of step 616. Preferably, stage four modifications includethe optional modifications of tuning the steering wheel and tuning thedriver's side knee bolster.

In some embodiments, the size, shape, and collapsing stiffness of thesteering wheel can be varied to help protect the occupants. Also, insome embodiments, the driver's side knee bolster can be repositioned andthe stiffness of the driver's side knee bolster can be tuned.

The passenger side knee bolster 1108 (see FIGS. 11 and 12) can only bemodified by stiffening knee bolster 1108. This is because any reductionin stiffness of passenger side knee bolster 1108 would invalidate theresults of second test 606. Preferably, the process is designed so thatno modification invalidates previous test results. Like other steps, thestage four modifications are preferably tuned until motor vehicle 100passes fourth test 614.

After motor vehicle 100 passes fourth test 614, the process proceeds tofifth test 618. Fifth test 618 determines whether motor vehicle 100 canprotect a male occupant during a frontal 48 km/h collision when the maleoccupant is wearing his seat belt. Preferably, a hypothetical maleoccupant is tested in fifth test 618 and in some embodiments an AM50%crash test dummy (which stands for American Male, 50 percentile) is usedto model the behavior of a hypothetical male occupant.

If motor vehicle 100 fails fifth test 618, then the process moves tostep 620 where stage five modifications can be made. Preferably, stagefive modifications do not invalidate any of the test results from any ofthe previous tests. In one embodiment, stage five modifications includetuning the seat belt.

In some embodiments, the position, anchor points and/or tension of theseat belt can be adjusted to help protect the male occupant. Like othersteps, the stage five modifications are preferably tuned until motorvehicle 100 passes fifth test 618.

One of the goals of method 600 is to avoid making a modification oradjustment during a current test that would invalidate a previoussuccessful test result. At this point in the preferred embodiment ofmethod 600, no other major modifications are available that would notinvalidate previous test results and any modification could invalidate aprevious successful test result. Therefore, there are no majormodifications available for the remaining tests and the process attemptsto confirm that motor vehicle 100 passes the next several tests.

After motor vehicle 100 passes fifth test 618, the process proceeds tosixth test 622, seventh test 624 and eighth test 626. Sixth test 622determines whether motor vehicle 100 can adequately protect a femaleoccupant during a frontal 48 km/h collision when the female occupant iswearing her seat belt. Preferably, a hypothetical female occupant istested in sixth test 622 and in some embodiments an AF5% crash testdummy (which stands for American Female 5 percentile) is used to modelthe behavior of a hypothetical female occupant.

Seventh test 624 determines whether motor vehicle 100 can protect a maleoccupant during a collision with an angled barrier at 40 km/h when themale occupant is not wearing his seat belt. Preferably, a hypotheticalmale occupant is tested in seventh test 624 and in some embodiments anAM50% crash test dummy (which stands for American Male, 50 percentile)is used to model the behavior of a hypothetical male occupant.

Eighth test 626 determines whether motor vehicle 100 can adequatelyprotect a female occupant during a collision with an offset barrier at40 km/h when the female occupant is wearing her seat belt. Preferably, ahypothetical female occupant is tested in eighth test 626 and in someembodiments an AF5% crash test dummy (which stands for American Female 5percentile) is used to model the behavior of a hypothetical femaleoccupant.

Again, because no modifications are available, the process determines ifmotor vehicle 100 passes sixth test 622, seventh test 624 and eighthtest 626. If motor vehicle 100 passes all of those tests, then theprocess proceeds to step 628 where the process concludes that motorvehicle 100 is qualified to use new firing map 300.

If motor vehicle 100 fails any one of the last three tests, then theprocess returns to a previous stage of modification. In someembodiments, this previous stage of modification can be determined byconsidering which modification would assist motor vehicle 100 in passingthe failed test. Preferably, the highest stage of modification isselected with a goal of minimizing the number of tests that areinvalidated. In other embodiments, this previous stage of modificationis predetermined and the process moves to a certain predeterminedmodification stage if motor vehicle 100 fails any of the last threetests. In a preferred embodiment, the process moves to third test 610 ifmotor vehicle 100 fails any of the last three tests.

Although, it is preferred that the inflatable restraint include only twodeployment modes, a first mode where the inflatable restraint does notdeploy and a second mode where the inflatable restraint is deployed witha delay, it is possible to provide embodiments where a simultaneousdeployment mode is used at some speed greater than 48 km/h. If asimultaneous deployment mode is used, it is preferred that thetransition zone between the simultaneous deployment mode and anyadjacent mote would not overlap with any regulation zone.

Using principles disclosed above, it is possible to provide a simplifiedinflatable restraint system that has more predictable characteristics,improved safety and the operation of which is easier to test andvalidate.

Each of the various components or features disclosed can be used aloneor with other components or features. Each of the components or featurescan be considered discrete and independent building blocks. In somecases, combinations of the components or features can be considered adiscrete unit.

While various embodiments of the invention have been described, it willbe apparent to those of ordinary skill in the art that may moreembodiments and implementations are possible that are within the scopeof the invention. Accordingly, the invention is not to be restrictedexcept in light of the attached claims and their equivalents.

1. A method for qualifying a motor vehicle for a crash test routinecomprising the steps of: determining whether the motor vehicle passes afirst test related to a hypothetical child passenger; and altering themotor vehicle using a first stage of modifications if the motor vehiclefails the first test.
 2. The method according to claim 1, furthercomprising the step of determining whether the motor vehicle passes asecond test related to a passenger; and altering the motor vehicle usinga second stage of modifications if the motor vehicle fails the secondtest; and wherein the second stage of modifications is different thanthe first stage of modifications.
 3. The method according to claim 2,further comprising the step of determining whether the motor vehiclepasses a third test related to an out of position passenger; andaltering the motor vehicle using a third stage of modifications if themotor vehicle fails the third test; and wherein the third stage ofmodifications is different than the first stage of modifications and thesecond stage of modifications.
 4. The method according to claim 3,further comprising the step of determining whether the motor vehiclepasses a fourth test related to a crash test conducted at a first speed;and altering the motor vehicle using a fourth stage of modifications ifthe motor vehicle fails the fourth test; and wherein the fourth stage ofmodifications is different than the first stage of modifications, thesecond stage of modifications and the third stage of modifications. 5.The method according to claim 4, further comprising the step ofdetermining whether the motor vehicle passes a fifth test related to acrash test conducted at a second speed; and altering the motor vehicleusing a fifth stage of modifications if the motor vehicle fails thefifth test; wherein the second speed is greater than the first speed;and wherein the fifth stage of modifications is different than the firststage of modifications, the second stage of modifications, the thirdstage of modifications and the fourth stage of modifications.
 6. Themethod according to claim 5, further comprising the step of determiningwhether the motor vehicle passes a sixth test related to a female crashtest conducted at the second speed.
 7. A method for preparing a motorvehicle for a crash test routine comprising a first test and a secondtest, the first test producing first test results; wherein first stagemodifications are available to help pass the first test; wherein secondstage modifications are available to help pass the second test; andwherein the second stage modifications are different than the firststage modifications.
 8. The method according to claim 7, wherein changesmade using the second stage modifications maintain the validity of thefirst test results.
 9. The method according to claim 7, wherein firststage modifications include modifying a shape of an instrument panelassociated with the motor vehicle.
 10. The method according to claim 7,wherein first stage modifications include modifying a first thighcontact point.
 11. The method according to claim 7, wherein first stagemodifications include modifying a height of a seat associated with themotor vehicle.
 12. The method according to claim 7, wherein first stagemodifications can be made by optionally changing any one of the groupconsisting essentially of: modifying a shape of an instrument panelassociated with the motor vehicle, modifying a first thigh contactpoint, and modifying a height of a seat associated with the motorvehicle.
 13. The method according to claim 7, wherein second stagemodifications include moving a position of a knee bolster associatedwith the motor vehicle.
 14. The method according to claim 7, whereinsecond stage modifications include moving a position of a windshieldassociated with the motor vehicle.
 15. The method according to claim 7,wherein second stage modifications include adjusting a stiffness of aknee bolster associated with the motor vehicle.
 16. The method accordingto claim 7, wherein second stage modifications can be made by optionallychanging any one of the group consisting essentially of: moving aposition of a knee bolster associated with the motor vehicle, moving aposition of a windshield associated with the motor vehicle, andadjusting a stiffness of a knee bolster associated with the motorvehicle.
 17. The method according to claim 7, wherein the first testincludes determining whether a hypothetical child enters a No Good Zone.18. The method according to claim 17, wherein the No Good Zone isassociated with a passenger side inflatable device.
 19. The methodaccording to claim 7, wherein the second test includes determiningwhether a hypothetical male passenger clears a windshield associatedwith the motor vehicle.
 20. The method according to claim 7, wherein thesecond test includes determining a pelvic stroke of a hypothetical malepassenger.